Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 196 insertions, 0 deletions

diff --git a/drivers/ata/ahci_dm816.c b/drivers/ata/ahci_dm816.c
new file mode 100644
index 0000000000..4cb70064fb
--- /dev/null
+++ b/drivers/ata/ahci_dm816.c
@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * DaVinci DM816 AHCI SATA platform driver
+ *
+ * Copyright (C) 2017 BayLibre SAS
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/pm.h>
+#include <linux/platform_device.h>
+#include <linux/libata.h>
+#include <linux/ahci_platform.h>
+
+#include "ahci.h"
+
+#define AHCI_DM816_DRV_NAME		"ahci-dm816"
+
+#define AHCI_DM816_PHY_ENPLL(x)		((x) << 0)
+#define AHCI_DM816_PHY_MPY(x)		((x) << 1)
+#define AHCI_DM816_PHY_LOS(x)		((x) << 12)
+#define AHCI_DM816_PHY_RXCDR(x)		((x) << 13)
+#define AHCI_DM816_PHY_RXEQ(x)		((x) << 16)
+#define AHCI_DM816_PHY_TXSWING(x)	((x) << 23)
+
+#define AHCI_DM816_P0PHYCR_REG		0x178
+#define AHCI_DM816_P1PHYCR_REG		0x1f8
+
+#define AHCI_DM816_PLL_OUT		1500000000LU
+
+static const unsigned long pll_mpy_table[] = {
+	  400,  500,  600,  800,  825, 1000, 1200,
+	 1250, 1500, 1600, 1650, 2000, 2200, 2500
+};
+
+static int ahci_dm816_get_mpy_bits(unsigned long refclk_rate)
+{
+	unsigned long pll_multiplier;
+	int i;
+
+	/*
+	 * We need to determine the value of the multiplier (MPY) bits.
+	 * In order to include the 8.25 multiplier we need to first divide
+	 * the refclk rate by 100.
+	 */
+	pll_multiplier = AHCI_DM816_PLL_OUT / (refclk_rate / 100);
+
+	for (i = 0; i < ARRAY_SIZE(pll_mpy_table); i++) {
+		if (pll_mpy_table[i] == pll_multiplier)
+			return i;
+	}
+
+	/*
+	 * We should have divided evenly - if not, return an invalid
+	 * value.
+	 */
+	return -1;
+}
+
+static int ahci_dm816_phy_init(struct ahci_host_priv *hpriv, struct device *dev)
+{
+	unsigned long refclk_rate;
+	int mpy;
+	u32 val;
+
+	/*
+	 * We should have been supplied two clocks: the functional and
+	 * keep-alive clock and the external reference clock. We need the
+	 * rate of the latter to calculate the correct value of MPY bits.
+	 */
+	if (hpriv->n_clks < 2) {
+		dev_err(dev, "reference clock not supplied\n");
+		return -EINVAL;
+	}
+
+	refclk_rate = clk_get_rate(hpriv->clks[1].clk);
+	if ((refclk_rate % 100) != 0) {
+		dev_err(dev, "reference clock rate must be divisible by 100\n");
+		return -EINVAL;
+	}
+
+	mpy = ahci_dm816_get_mpy_bits(refclk_rate);
+	if (mpy < 0) {
+		dev_err(dev, "can't calculate the MPY bits value\n");
+		return -EINVAL;
+	}
+
+	/* Enable the PHY and configure the first HBA port. */
+	val = AHCI_DM816_PHY_MPY(mpy) | AHCI_DM816_PHY_LOS(1) |
+	      AHCI_DM816_PHY_RXCDR(4) | AHCI_DM816_PHY_RXEQ(1) |
+	      AHCI_DM816_PHY_TXSWING(3) | AHCI_DM816_PHY_ENPLL(1);
+	writel(val, hpriv->mmio + AHCI_DM816_P0PHYCR_REG);
+
+	/* Configure the second HBA port. */
+	val = AHCI_DM816_PHY_LOS(1) | AHCI_DM816_PHY_RXCDR(4) |
+	      AHCI_DM816_PHY_RXEQ(1) | AHCI_DM816_PHY_TXSWING(3);
+	writel(val, hpriv->mmio + AHCI_DM816_P1PHYCR_REG);
+
+	return 0;
+}
+
+static int ahci_dm816_softreset(struct ata_link *link,
+				unsigned int *class, unsigned long deadline)
+{
+	int pmp, ret;
+
+	pmp = sata_srst_pmp(link);
+
+	/*
+	 * There's an issue with the SATA controller on DM816 SoC: if we
+	 * enable Port Multiplier support, but the drive is connected directly
+	 * to the board, it can't be detected. As a workaround: if PMP is
+	 * enabled, we first call ahci_do_softreset() and pass it the result of
+	 * sata_srst_pmp(). If this call fails, we retry with pmp = 0.
+	 */
+	ret = ahci_do_softreset(link, class, pmp, deadline, ahci_check_ready);
+	if (pmp && ret == -EBUSY)
+		return ahci_do_softreset(link, class, 0,
+					 deadline, ahci_check_ready);
+
+	return ret;
+}
+
+static struct ata_port_operations ahci_dm816_port_ops = {
+	.inherits = &ahci_platform_ops,
+	.softreset = ahci_dm816_softreset,
+};
+
+static const struct ata_port_info ahci_dm816_port_info = {
+	.flags		= AHCI_FLAG_COMMON,
+	.pio_mask	= ATA_PIO4,
+	.udma_mask	= ATA_UDMA6,
+	.port_ops	= &ahci_dm816_port_ops,
+};
+
+static const struct scsi_host_template ahci_dm816_platform_sht = {
+	AHCI_SHT(AHCI_DM816_DRV_NAME),
+};
+
+static int ahci_dm816_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ahci_host_priv *hpriv;
+	int rc;
+
+	hpriv = ahci_platform_get_resources(pdev, 0);
+	if (IS_ERR(hpriv))
+		return PTR_ERR(hpriv);
+
+	rc = ahci_platform_enable_resources(hpriv);
+	if (rc)
+		return rc;
+
+	rc = ahci_dm816_phy_init(hpriv, dev);
+	if (rc)
+		goto disable_resources;
+
+	rc = ahci_platform_init_host(pdev, hpriv,
+				     &ahci_dm816_port_info,
+				     &ahci_dm816_platform_sht);
+	if (rc)
+		goto disable_resources;
+
+	return 0;
+
+disable_resources:
+	ahci_platform_disable_resources(hpriv);
+
+	return rc;
+}
+
+static SIMPLE_DEV_PM_OPS(ahci_dm816_pm_ops,
+			 ahci_platform_suspend,
+			 ahci_platform_resume);
+
+static const struct of_device_id ahci_dm816_of_match[] = {
+	{ .compatible = "ti,dm816-ahci", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ahci_dm816_of_match);
+
+static struct platform_driver ahci_dm816_driver = {
+	.probe = ahci_dm816_probe,
+	.remove_new = ata_platform_remove_one,
+	.driver = {
+		.name = AHCI_DM816_DRV_NAME,
+		.of_match_table = ahci_dm816_of_match,
+		.pm = &ahci_dm816_pm_ops,
+	},
+};
+module_platform_driver(ahci_dm816_driver);
+
+MODULE_DESCRIPTION("DaVinci DM816 AHCI SATA platform driver");
+MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>");
+MODULE_LICENSE("GPL");